Clinical Characteristics Of Patients With Primary Sj(o|")gren's Syndrome Associated Renal Tubular Acidosis And Neurological Involvement

Objective:This study aimed to describe the characteristics of primary Sjogren's syndrome(pSS)-associated renal tubular acidosis(RTA),peripheral neuropathy(PN),and neuromyelitis optica spectrum disorders(NMOSD).We also identified potential risk factors of these extraglandular involvements in Chinese patients with pSS.Method:We enrolled patients with pSS-RTA,pSS-PN,and pSS-NMOSD fulfilling the inclusion and exclusion criteria from 221 rheumatology centers in China.Demographic data,disease characteristics,laboratory data,disease activity assessment,and baseline treatment were collected.A cross-sectional analysis was used to summarize the baseline characteristics.pSS patients without renal or neurological involvements from SICCA database were included as a control group.A nested case-control study was conducted.Logistics regression was used to identify the risk factors.Result:In this study,257 patients with pSS-RTA,198 patients with pSS-PN,and 45 patients with pSS-NMOSD were enrolled.98.4%patients with pSS-RTA were female and the mean age at baseline was 46.7±14.1 years old.Impaired renal function was found in 30/120 patients.The median ESSDAI was 9(5,15)and the percentage of glucocorticoid use at baseline was 68.5%.The independent risk factors of pSS-RTA included disease onset age ? 45 years old[OR 2.04,95%CI(1.47-2.57),P<0.001],arthritis[OR 1.55,95%CI(1.10-2.20),P=0.013],positive anti-SSB antibody[OR 1.75,95%CI(1.32-2.33),P<0.001],positive anti-Ro-52 antibody[OR 1.42,95%CI(1.01-2.00),P=0.044],anemia[OR 1.68,95%CI(1.28-2.21),P<0.001],elevated erythrocyte sedimentation rate[OR 1.70,95%CI(1.12-2.60),P=0.013],high alkaline phosphatase level[OR 2.25,95%CI(1.34-3.79),P=0.002],and hyperglobulinemia[OR 1.40,95%CI(1.03-1.89),P=0.030].96.0%patients with pSS-PN were female and the mean age at baseline was 54.6±12.3 years old.The median ESSDAI was 14(7,20.2)and the percentage of glucocorticoid use at baseline was 62.2%.The independent risk factors of pSS-PN were disease onset age>45 years old[OR 1.38,95%CI(1.02-1.87),P=0.035],comorbid stroke[OR 2.55,95%CI(1.11-5.86),P=0.027],positive anti-RNP antibody[OR 1.72,95%CI(1.00-2.93),P=0.048],gland enlargement[OR 1.45,95%CI(1.03-2.04),P=0.031],arthritis[OR 5.35,95%CI(3.94-7.27),P<0.001],and hemolytic anemia[OR 2.62,95%CI(1.05-6.51),P=0.039].All the patients with pSS-NMOSD were female and the mean age at baseline was 48.4±9.3 years old.The median ESSDAI was 15.5(10,25.2)and the percentage of glucocorticoid use at baseline was 73.3%.The independent risk factors of pSS-NMOSD included disease onset age ? 45 years old[OR 1.94,95%CI(1.04-3.62),P=0.037],positive anti-centromere antibodies[OR 2.86,95%CI(1.07-7.67),P=0.037],and arthritis[OR 3.23,95%CI(1.65-6.36),P=0.001].Conclusion:This is the largest study on RTA and neurological manifestation in patients with pSS.Baseline characteristics and risk factors were obtained.Regular screen was recommended in patients with risk factors of pSS-RTA,pSS-PN,and pSS-NMOSD.